• Title/Summary/Keyword: Fair rate

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A study on improving fairness and congestion control of DQDB using buffer threshold value (버퍼의 문턱치값을 이용한 DQDB망의 공평성 개선 및 혼잡 제어에 관한 연구)

  • 고성현;조진교
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.22 no.4
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    • pp.618-636
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    • 1997
  • DQDB(Distributed Queue Dual Bus) protocol, the IEEE 802.6 standard protocol for metropolitan area networks, does not fully take advantage of the capabilities of dual bus architecture. Although fairness in bandwidth distribution among nodes is improved when using so called the bandwidth balancing mechanism, the protocol requires a considerable amount of time to adjust to changes in the network load. Additionally, the bandwidth balancing mechanism leaves a portion of the available bandwidth unused. In a high-speed backbone network, each node may act as a bridge/ router which connects several LANs as well as hosts. However, Because the existence of high speed LANs becomes commonplace, the congestionmay occur on a node because of the limitation on access rate to the backbone network and on available buffer spaces. to release the congestion, it is desirable to install some congestion control algorithm in the node. In this paper, we propose an efficient congestion control mechanism and fair and waster-free MAC protocol for dual bus network. In this protocol, all the buffers in the network can be shared in such a way that the transmission rate of each node can be set proportional to its load. In other words, a heavily loaded node obtains a larger bandwidth to send the sements so tht the congestion can be avoided while the uncongested nodes slow down their transmission rate and store the incoming segments into thier buffers. this implies that the buffers on the network can be shared dynamically. Simulation results show that the proposed probotol significantly reduces the segment queueing delay of a heavily loaded node and segment loss rate when compared with original DQDB. And it enables an attractive high throughput in the backbone network. Because in the proposed protocol, each node does not send a requet by the segment but send a request one time in the meaning of having segments, the frequency of sending requests is very low in the proposed protocol. so the proposed protocol signigificantly reduces the segment queuing dely. and In the proposed protocol, each node uses bandwidth in proportion to its load. so In case of limitation of available buffer spaces, the proposed protocol reduces segment loss rate of a heavily loaded node. Bandwidth balancing DQDB requires the wastage of bandwidth to be fair bandwidth allocation. But the proposed DQDB MAC protocol enables fair bandwidth without wasting bandwidth by using bandwidth one after another among active nodes.

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A Weighted Fair Queuing Scheduler Guaranteeing Differentiated Packet Loss Rates (차별화된 패킷 손실률을 보장하는 가중치 기반 공정 큐잉 스케줄러)

  • Kim, Tae Joon
    • Journal of Korea Multimedia Society
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    • v.17 no.12
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    • pp.1453-1460
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    • 2014
  • WFQ (Weighted Fair Queuing) provides not only fairness among traffic flows in using bandwidth but also guarantees the Quality of Service (QoS) that individual flow requires, which is why it has been applied to the resource reservation protocol (RSVP)-capable router. The RSVP allocates an enough resource to satisfy both the rate and end-to-end delay requirements of the flow in the condition of no packet loss, and the WFQ scheduler guarantees those QoS requirements with the allocated resource. In practice, however, most QoS-guaranteed services allow a degree of packet loss, especially from 0.1% to 3% for Voice over IP. This paper discovers that the packet loss rate of each traffic flow is determined by only its time-stamp adjustment value, and then enhances the WFQ to provide a differentiated packet loss guarantee under general traffic conditions in terms of both traffic characteristics and QoS requirements. The performance evaluation showed that the proposed WFQ could increase the utilization of bandwidth by 8~11%.

Adaptive Multiple TCP-connection Scheme to Improve Video Quality over Wireless Networks

  • Kim, Dongchil;Chung, Kwangsue
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.8 no.11
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    • pp.4068-4086
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    • 2014
  • Due to the prevalence of powerful mobile terminals and the rapid advancements in wireless communication technologies, the wireless video streaming service has become increasingly more popular. Recent studies show that video streaming services via Transmission Control Protocol (TCP) are becoming more practical. TCP has more advantages than User Diagram Protocol (UDP), including firewall traversal, bandwidth fairness, and reliability. However, each video service shares an equal portion of the limited bandwidth because of the fair sharing characteristics inherent in TCP and this bandwidth fair sharing cannot always guarantee the video quality for each user. To solve this challenging problem, an Adaptive Multiple TCP (AM-TCP) scheme is proposed in this paper to guarantee the video quality for mobile devices in wireless networks. AM-TCP adaptively controls the number of TCP connections according to the video Rate Distortion (RD) characteristics of each stream and network status. The proposed scheme can minimize the total distortion of all participating video streams and maximize the service quality by guaranteeing the quality of each video streaming session. The simulation results show that the proposed scheme can significantly improve the quality of video streaming in wireless networks.

Fuzzy Logic Based Buffer Management Algorithm to Improve Performance of Internet Traffic over ATM Networks (ATM 네트워크에서 인터넷 트래픽 성능 향상을 위한 퍼지기반 버퍼 관리 알고리즘)

  • 김희수;김관웅;박준성;배성환;전병실
    • Journal of the Institute of Electronics Engineers of Korea TC
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    • v.40 no.9
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    • pp.358-365
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    • 2003
  • To support Internet traffic efficiently over ATM networks, Guaranteed Frame Rate(GFR) has been proposed in the ATM Forum. GFR provides minimum rate guarantees to VCs and allows any excess bandwidth in the network to be shared among the contending VCs in a fair manner. In this paper, we proposed a new fuzzy logic based buffer management algorithm that provides MCR guarantee and fair sharing to GFR VCs. A key feature of proposed algorithm is its ability to accept or drop a new incoming packet dynamically based on buffer condition and load ratio of VCs. This is achieved by using fuzzy logic controller for the production of a drop factor. Simulation results show that proposed scheme significantly improves fairness and TCP throughput compared with previous schemes.

Aggressive Subchannel Allocation Algorithm for Optimize Transmission Efficiency Among Users in Multiuser OFDMA System (다중 사용자 OFDMA 시스템에서의 사용자간 전송효율 최적화를 위한 Aggressive Subchannel Allocation 알고리즘)

  • Ko Sang-Jun;Heo Joo;Chang Kyung-Hi
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.31 no.6A
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    • pp.617-626
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    • 2006
  • In this paper, we propose an ASA(Aggressive Subchannel Allocation) algorithm, which is an effective dynamic channel allocation algorithm considering all user's channel state to maximize downlink sector throughput in OFDMA system. We compare an ASA algorithm with Round Robin, ACG(Amplitude Craving Greedy), RCG(Rate Craving Greedy) and GPF(General Proportional Fair) in the 2-tier environment of FRF(Frequency Reuse Factor) 1 and then analyze the performance of each algorithms, through compute simulation. Simulation results show that the proposed ASA algorithm gets 58 %, 190 %, 130 % and 8.5 % better sector throughput compared with the Round Robin, ACG, RCG and GPF respectively.

System Implementation for Fair Automatic Heating Operation Based on Spatial Distributing and Zonal Calorie Measuring (공간분활 및 영역열량측정에 의한 공평 자동난방운영시스템 구현)

  • Han, Sang Cheol;Ryu, Kwang Ryol
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.23 no.8
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    • pp.910-916
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    • 2019
  • This paper describes the system implementation of the heating operation based on spatial distributing and zonal calorie measuring and analyzing of houses to calculate the fair amount of the heating meterage automatically. The heating space is distributed into 4 zones, which the flow rate and calories are checked by one meter respectively. The system is composed of a heating sources, adjuster of thermostat, valve controller, PC converter and total monitering. The returning temperature in the spatial zones is measured for the heating calorie to calculate the zonal calories according to the rooms temperature. The proposed system results in error by 1% or less in comparing with the dedicated experimental equipment, and reduces energy cost by 7% from conventional system. The fair checking system will be enhanced with building energy management system in the future.

Rate-based Processor Reservation Technique for Multimedia Applications (멀티미디어 응용을 위한 요구비율 기반 프로세서 예약 기법)

  • Park, Young-Il;Ha, Rhan
    • Proceedings of the Korean Information Science Society Conference
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    • 2000.04a
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    • pp.86-88
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    • 2000
  • 멀티미디어 태스크는 기존 범용 운영 체제의 시분할 스케줄러에서 만족시킬 수 없는 시간적 요구사항을 가진다. 이런 태스크를 기존의 시분할 태스크와 함께 서비스하기 위해서는 새로운 스케줄링 프레임워크가 필요하다. FQ(Fair Queueing)은 태스크의 공유비율에 비례하여 자원을 할당하는 방법으로 이질적인 태스크(멀티미디어 태스크, 일반 시분할 태스크)가 공존하는 개방적인 환경에서의 스케줄링 정책으로 적합하다는 특징이 있다. 본 논문에서는 FQ의 종류인 WFQ(Weighted Fair Queueing)를 개선하여 하나의 스케줄러에서 다른 두 부류의 태스크를 모두 처리하는 요구비율 기반의 프로세서 예약 기법을 제안한다. 실시간 태스크와 시분할 태스크를 처리하기 위해서 실시간 부류의 태스크를 우선적으로 배치하고, 실시간 부류 태스크의 실행 사이에 시분할 태스크를 스케줄하여 실시간 태스크에 대해서 보장된 서비스를, 시분할 태스크에 대해서는 이 태스크에 할당된 예약만큼의 프로세서 시간을 제공한다. 모의 실험에서는 제안한 프로세서 예약 방식이 실시간 태스크와 시분할 태스크를 효율적으로 처리하며 기존의 WFQ보다 더 안정적임을 보인다.

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Proportional Fair Scheduling Algorithm in OFDMA-Based Wireless Systems with QoS Constraints

  • Girici, Tolga;Zhu, Chenxi;Agre, Jonathan R.;Ephremides, Anthony
    • Journal of Communications and Networks
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    • v.12 no.1
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    • pp.30-42
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    • 2010
  • In this work we consider the problem of downlink resource allocation for proportional fairness of long term received rates of data users and quality of service for real time sessions in an OFDMA-based wireless system. The base station allocates available power and subchannels to individual users based on long term average received rates, quality of service (QoS) based rate constraints and channel conditions. We formulate and solve a joint bandwidth and power optimization problem, solving which provides a performance improvement with respect to existing resource allocation algorithms. We propose schemes for flat as well as frequency selective fading cases. Numerical evaluation results show that the proposed method provides better QoS to voice and video sessions while providing more and fair rates to data users in comparison with existing schemes.

The Impact of Blockchain Technology on the Music Industry

  • Kim, Kenneth Chi Ho
    • International journal of advanced smart convergence
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    • v.8 no.1
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    • pp.196-203
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    • 2019
  • We have reviewed the potential impact of blockchain technology on the music industry by analyzing the views of academia and the industry experts. The music industry had rapid changes from the physical market to the digital market in the past decades. The consumers download and stream music online and mobile during the digital dominant market. While streaming music has been recently growing at a fast rate, fair distribution of revenue to the artists continues to be an issue. Some industry experts believe that the issue of fair distribution of revenue to the artist may be resolved using blockchain technology, while some are skeptical about the application or the duration of impact. The blockchain may enhance speedier payment using smart contracts, provide additional revenue and promote the music if excellent fan support is achieved. The positive impact on the music industry may only be possible if there are detailed consideration of the industry and careful understanding of the customers.

Perception on Plagiarism among Faculty Members and Research Scholars in Higher Educational Institutions of Dindigul District: A Study

  • Dhanavandan, Sadagopan
    • International Journal of Knowledge Content Development & Technology
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    • v.12 no.2
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    • pp.77-98
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    • 2022
  • These papers surveyed the respondents' Awareness and perception of Plagiarism among the Faculty members and research scholars of higher educational institutions in Dindigul District, Tamil Nadu. The 500 questionnaires were distributed among the participants, 456 questionnaires were filled and returned for usable by the respondents and remaining not replied. The responses rate is 91.2%. Further among 222 Male re- spondents, 11.18% of them are having Aware, 10.75% of them in Learning, 10.53% are with Fair and 76(16.23%) of them are Expert. Similarly out of 234 Female respondents, 16.45% of them has No Idea, 7.02% of them have Aware, 10.09% of them in Learning, 8.99% are with Fair and 8.77% of them are Expert.